Duplex grating for pipeless furnaces



' w. J. JOHNSON. DUPLEX GRATING FOR PIPELESS FURNACES.

APPLICATION FILED MAR. 27.1919.

Patented Oct. 18, 1921.

2 SHEETS-SHEET I.

172003507 @JJ/zmara .W. J. JOHNSON.

DUPLEX GRATING FOR PIPELESS FURNACES.

APPLICATION FILED MAR.27, 1919.

WESLEY J. JOHNSON, 013 CHICAGO,

ILLINOIS.

DUPLEX GRATING FOR PIPELESS FURNACES.

Specification of Letters Patent.

Patented Oct. 18, 1921.

Application filed March 27, 1919. Serial No. 285,514.

To all whom it may concern:

Be it known that I, lVnsLnY J. JOHNSON, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented certain new and useful Improvements in Duplex Gratings forPipeless Furnaces, of which the following is the specification.

This invention relates to pipeless furnaces and more particularly to thegrating adapted to be positioned in the floor or other suitable place topermit the hot air to enter the room from the furnace, and the cooler orcold air to pass from the room through a portion of the grating back tothe furnace to be reheated. l

In the conventional type of duplex grating for pipeless furnaces, theupper end or opening of the pipe conducting the hot air from the furnaceto the room is positioned centrally of the grating frame and has anequal space on all sides thereof, covered with grating through which thecold air passes on its way back to the furnace to be again heated beforebeing returned to the room. through the hot air pipe. Since the upperportion of the framework or oifset surrounidng the furnace doors (toallow the necessary radius for the outer casing), and connecting theinner casing with the outer casing, forms an obstructing shelf orbarrier opposing the passage of the cold air returning from the room tothe furnace at this particular part of the cold air space, it will beseen that the returning cold air cannot pass directly down at this sideof the furnace, but must be deflected sidewise to clear said shelf orbarrier and then mingle with the cold air at the sides of the furnace.This conventional type is therefore objectionable for many reasons,among which may be mentioned the loss of efficiency of the furnace, dueto the inability of all of the cold air to pass freely and directly downto the lower part of the furnace; the inability of workmen to locate thegrating well up'in the corner of a room or closely alongside a wall whena wall or other obstruction is encountered in the basement, and preventsetting the furnace in exactly the spot desired; theinability of theoccupants of the house to comfortably use the duplex grating as a footwarmer, due to the presence of downwardly passing currents of cold airon all exterior sides of the hot air stantially contacts withsimplicity,

plpe; as well as other objections not specifically mentloned. All ofthese objections and others are entirely obviated in my improvedgrating, 1n which I so place the hot air pipe with relation to theexterior cold air grating that the circumference of the former subthemarginal portion of the latter on that side of the grating ad acent thesaid obstructing shelf or barrler above the fire door.

Among the objects of my invention, therefore, is to provide a duplexrating of such form as to greatly increase t the furnace by causing thereturning cold air to pass directly to those parts of the furnace bestcapable of effectively handling the same for quick reheating; further toprovide such grating that workmen may readily place the furnace inposition to bring the grating into corners or other desirable placesdifficult to reach with the old form of grating; further, to makepossible the comfortable warming of ones feet over the hot air pipewithout of cold air; further, to increase the amount of air delivered tothe apparatus; further,

to provide a duplex grating of maximum such further objects, advantages,and capabilities as will later more fully appear.

My inventlon further resides in the combination, construction, andarrangement ofparts illustrated in the accompanying drawing, and, whileI have shown therein a preferred embodiment, I desire the same to beunderstood as illustrative only, and susceptible of modificationand'change without departing from the spirit of my invention.

In the drawings:

Figure 1 is vertical longitudinal section through a central plane of afurnace equipped with my improved grating and showing in dotted linesthe imaginary position that wouldbe occupied by the old conventionaltype of grating and connections.

Fig. 2 is a perspective View of the exterior of a pipeless. furnaceshowing the obstruction to the downwardly passing cold air at the frontof the furnace.

Fig. 3 is a plan view of my improved grating, the dotted lines showingthe imagi nary position of the exterior frame of the old conventionaltype with relation to the grating of the hot air pipe.

e efficiency of encounterin currents economy,and eflicaciousness; and

. is preferably round (although other shapes,

' 12 over the furnace doors.

Fig. 4 is a sectional view of Fig. 3, taken through the center of thegrating, for the hot air pipe.

Referring more in detail to the drawing, A designates generally apipeless furnace comprising the outer casing 1, the inner casing 2,spaced therefrom, (between which casings is the cold air passage 3), thefire pot it (having the customary fire-grate 5, combustion chamber 6 andsmoke flue 7), and the usual frame work 8 surrounding the fire door 9,the clean out and draftcheck door 10, and ash door 11, the upper part ofwhich frame work is designated by '12. This frame work, as will beunderstood, affords proper radius for the outer casing withoutobstructing the fire, cleanout, and ash doors.

My improved grating is designated at 13, and comprises two mainsections, to wit, the inner section 14. for thehot air pipe 15, and theouter section 16 for the cold air space or passage 3; the hot air pipebeing flared as shown at 17 tooompensate for the difference in diameterbetween its top and the inner casing of the furnace. As shown in Fig. 3,the inner sectionll of the grating may obviously be availed of) and ispositioned with one side substantially in contact with the marginalportion of the outer section 16, whereby to practically eliminate thecold air grating at that portion of my grating falling nearest to thetop plate 12 of the frame work 8 spacing the outer casing from the innercasing. The very small amount of grating space (if any) existing at thisfront edge of the cold air grating is so small as to be practicallynegligible. The result of this structure is that the cold air returningto the furnace through the cold air grating will be substantially allforced to pass through those parts of the grating lying, atthe two sidesand rear of the hot air pipe and thus carried directly to those parts ofthe furnace best able to handle it, that is, through those parts of thecold air space 3, unobstructed by the top plate It will thus be seenthat the large volume of cold air carried directly against the top plate12 in the old conventional type of grating is eliminated, andsubstantially all of the cold air thrown directly into those passagesable to handle it with the greatest efficiency. This will addapproximately 25% more air delivered to the apparatus, and thus greatlyincrease its capacity.

The grating may obviously be formed in many ways, such as by casting itwith the cold air outer section and marginal frame all in one piece,provided with an opening and appropriate flange within which the innersection 14: rests, the inner section also being cast in one piece, asshown in Figs.

3 and 4; or the grating may be built up of separate bars of steel orother material secured in an outer frame, also of the form of Fig. 3; orif desired, the entire grating may be made integral and rest upon thetop of the hot air pipe, with which latter it has appropriate connectionby means of a flange piece 20, as shown in Fig. 1.

As is readily seen in Fig. 1, the bulk of the cold is thrown to the rearof the furnace, the remainder being substantially all thrown to thesides, which parts obviously through the medium of the space 3 conductsit directly downward to the bottom of the inner casing and up in contactwith the fire bowl. As will be understood'from the dotted line in Fig.1, (which represent the location of the grating and connection with theold conventional type of grating), my new type of grating, enables theworkman to more readily locate itin corners, even though protrudingwalls or the like be encountered in the basement. This enables theproper placing of the grating with relation to partition walls andcorners. Also, due to the absence of the downwardly passing'currents ofcold air at the front edge of my grating, one can use the warm airportion as a foot warmer without discomfort or danger from drafts.

From the above it will be seen thatlhave produced a form of grating thateliminates all of the objections of the old conventional type, one whichis cheap to manufacture, simple in construction, possesses maximumefiiciency, increases the capacity of the furnace, and one which greatlyenlarges the field of possibilities ofthepipeless furnace.

Having now describedmy invention, I claim: 7

1. A duplex grating, for use with pipeless furnaces having a warm airjacket and a cold air jacket substantially surrounding said first namedjacket at its emergent end, comprising a cold air section and a warm airsection, said sections adapted to cover the open ends of the coldandwarm air jackets respectively, the warm air section being positionedadjacent one side of but within-the cold air section, whereby to causethe cold air to substantially all pass directly to the heating portionsof the furnace for immediate heating. 1 v

2. A duplex gratingfor use with pipeless furnaces having a warm airjacket and a cold air jacket substantially surrounding the same at itsemergent end, comprising a cold air section having a marginal portion,and a warm air section lying within said cold air section andsubstantially touching said ma ginal portion on one side of the grating,

the warm air section being entirely sur-.

rounded by the cold air section except at said touching point, wherebyto-cause the cold air to pass downwardly outside of the hot air sectionon all sides except at the said touching side to prevent passage of coldair to non-heating portions of the furnace.

3. In combination, a hot air passage for conducting heated air from aheat generating means to a room, a cold air passage for conducting coldair from the room to said means and lying outside of said hot airpassage, and a common grating over said passages, said hot air passagebeing so joined With the grating with relation to the cold air passagethat substantially no cold air will be permitted to pass down at thefront, but will be permitted to pass down freely on all other sides topartially surround the heat generating means.

4-. In combination, a hot air passage, a

, cold air passage, a common grating over said passages, the hot airpassage being joined with the grating at one side thereof whereby tocause the cold air substantially all to pass down the cold air passageat the sides and back, and to throw the bulk of the grating toward therear of the hot air passage to facilitate placing the grating in thecorners of rooms and in convenient position with relation to partitionsand walls.

5. A duplex grating, for use with pipeless furnaces having a Warm airjacket and a cold air jacket partially surrounding the warm air jacketfrom the emergent end to the heating portion of the furnace, comprisingan openwork warm air section and an openwork cold air section adapted tocover the open ends of the warm and cold air jackets respectively, thewarm air section being positioned to one side of the cold air sectionand with one of its sides substantially touching one of the marginalside portions of the grating, so that the cold air will be substantiallyexcluded from passing downwardly along said touching side of the warmair section, to non-heating portions of the furnace.

In witness whereof, I hereunto subscribe my name to this specification.

WESLEY J. JOHNSON.

